The present invention relates generally to a combined detent and neutral switch mechanism for use in a manually controlled transmission.
As the vehicle operator moves a shift lever though the shift pattern, the shift lever moves an operatively connected shift fork extension. The moving shift fork extension in turn selectively engages a shift fork which moves clutch collars into engagement with a gear, causing a gear shift.
Prior art manual transmissions assemblies utilize both detent mechanisms and neutral switches, which are separate components within the manual transmission. A detent mechanism provides feedback, or a shift feel, to indicate to the vehicle operator where he is in the shift pattern. As a shift fork extension is moved during a shift, a detent pin coacts with a contoured surface in the shift fork extension and provides resistance to the movement of the shift fork extensions.
When shifting gears in a manual transmission assembly, only one shift fork extension can move at a time. It is therefore desirable that the shift fork extensions, and the transmission, be in the neutral position when a shift occurs. A neutral switch is used to provide feedback that the transmission is in neutral. The separate detent and neutral switch mechanisms require additional parts to assemble the manual transmission. Therefore, undue time is needed to assemble and repair the transmission.
Hence, there is a need in the art for a combined detent and neutral switch mechanism for use in a manually controlled transmission.
The present invention relates to a combined detent and neutral switch mechanism for use with a manually controlled transmission.
A manual transmission includes a plurality of shift fork extensions. Each shift fork extension has a neutral detent notch and at least one in-gear detent notch, with detent peaks positioned therebetween. When the transmission is in the neutral position, all the neutral detent notches are aligned.
The combined detent and neutral switch mechanism includes a roller detent pin attached to a roller spring. When the transmission is put into gear, the selected shift fork extension translates and the detent pin engages the in-gear detent notch corresponding to the selected gear to resiliently maintain the shift fork extension into the desired in-gear position.
The neutral detent notches, in-gear detent notches, and detent peaks are all formed to different depths. The neutral detent notches are formed to the deepest depth, the detent peaks are formed to the shallowest depth, and the in-gear detent notches are formed to an intermediate depth. As the detent pin travels over the contoured surfaces of the shift fork extension, the detent pin biases the roller spring upwardly and downwardly to resist the movement of the shift fork extension and create a xe2x80x9cshift feel.xe2x80x9d
The combined detent and neutral switch mechanism also includes a neutral position switch to indicate when the manual transmission is in neutral. As the selected shift fork extension is translated, the detent pin attached to the roller spring moves in an upwardly and downwardly direction.
When the detent pin is located in an in-gear detent notch or on a detent peak, more upward force is applied to the roller spring and the roller spring contacts the position switch. This indicates either that the transmission is in a gear or that a shift is in progress. If all of the neutral detent notches are aligned (the transmission is in neutral) the detent pin lowers into the aligned neutral detent notches, and the roller spring disengages from the position switch, indicating that the transmission is in neutral and that it is safe to make a gear shift, or the switch could be reversed such that it is only engaged when the transmission is in neutral.
Accordingly, the present invention provides a combined detent and neutral switch mechanism for use in a manually controlled transmission
These and other features of the present invention will be best understood from the following specification and drawings.